Stable anhydrous topically-active composition and suspending agent therefor

ABSTRACT

An anhydrous, topically-effective composition that resists phase separation and exhibits improved properties comprising a topically-active compound, such as an astringent salt; an improved suspending agent comprising a finely-divided silica and a suspending wax composition; and a suitable volatile liquid carrier, such as a volatile silicone or a volatile hydrocarbon. The suspending wax composition comprises a wax, an ester including at least 10 to about 32 carbon atoms and a volatile liquid carrier. The anhydrous, topically-effective composition is useful in topical cosmetic and medicinal preparations, such as antiperspirants, sunscreens and topical drug products, and is especially useful in cosmetic and medicinal preparations wherein an insoluble topically-active compound is dispersed throughout a liquid phase.

CROSS-REFERENCE TO A RELATED APPLICATION

This application is a continuation-in-part of copending application Ser.No. 360,418, filed on Jun. 2, 1991.

FIELD OF THE INVENTION

The present invention is directed to an anhydrous composition includinga new and improved suspending agent, wherein the anhydrous compositioneffectively resists phase separation and is useful for the topicaldelivery of a topically-active component. More particularly, theanhydrous composition of the present invention is an unexpectedly stablesuspension useful for the improved topical delivery of atopically-active compound, either cosmetic or medicinal, to the skin.Therefore, in general, the present invention is directed to ananhydrous, topically-effective composition comprising a topically-activecompound, such as an antiperspirant compound, like a powdered astringentsalt; a suspending agent including a finely-divided silica and asuspending wax composition; and a suitable volatile liquid carrier. Thetopically-effective composition effectively resists phase separation;reduces whitening and staining to skin and clothing after topicalapplication; effectively delivers the topically-active compound; andexhibits superior sensory properties.

BACKGROUND OF THE INVENTION

As set forth in the Deckner U.S. Pat. No. 4,563,346, an idealcomposition for delivery a topically-active compound to skin or hairshould be stable and should deliver the topically-active compound suchthat it adheres to the skin or hair while topically-inactive ingredientsevaporate or are otherwise removed from the area of application.Topically-delivered active compounds, such as cosmetics, like anantiperspirant compound, and topical medications, like an antibacterialor an anti-inflammatory, traditionally have been prepared as eitheroil-in-water emulsions or water-in-oil emulsions. However,topically-effective compositions prepared as emulsions feel wet or oilywhen applied to the skin, and often remain sticky after the compositioncarrier vehicle evaporates. Furthermore, emulsion-type compositionsrequire a relatively long time to dry after topically application. Inaddition, many emulsion-type compositions leave a white residue oncontacted skin or clothing, and actually stain clothing.

Nonemulsified anhydrous compositions, like antiperspirants, are known inthe art. For example, non-emulsified, oil-based topically-effectivecompositions are available, however these products often require shakingprior to each use in order to redisperse the insoluble topically-activecompound that has separated from the composition. For example, U.S. Pat.No. 3,873,686 discloses an anhydrous, liquid or cream antiperspirantcomposition comprising an alcohol-soluble aluminumchlorohydroxide-polyol complex in an anhydrous ethanol vehicle.Similarly, U.S. Pat. No. 4,137,306 discloses the above-describedanhydrous antiperspirant composition in solid stick form. U.S. Pat. Nos.4,053,581; 4,065,564; and 4,073,880 disclose liquid anhydrousantiperspirant compositions useful as pump-spray and roll-on products,wherein the antiperspirant compounds are solubilized in a vehicleincluding ethanol and a sufficient amount of a volatile or anon-volatile silicone liquid to reduce tackiness of the antiperspirant.U.K. Patent Application No. 2018590A describes an anhydrousantiperspirant spray composition including from 60% to 90% of a volatilecyclic silicone in order to improve composition efficacy by increasingadherence of the antiperspirant composition to the skin and hair.Nevertheless, although suspending agents are included in each of theabove-cited references, the antiperspirant compositions require shakingbefore use in order to redisperse the separated antiperspirant compound.

Stable, nonseparating antiperspirant compositions also are known in theart. U.S. Pat. No. 4,749,569 discloses an extrudable antiperspirantpaste, or cream, composition stabilized against phase separation bythickening the antiperspirant composition with from 4.6% to 9.5% of afinely-divided silica and from 2% to 25% of a quaternized three-layerclay exfoliated with a polar solvent. If a finely-divided silica is usedas the sole thickening, or suspending, agent, then an unstable productresults. Therefore, an additional suspending agent, like an organoclay,is included in the composition. However, the presence of an organoclayin an antiperspirant composition is a principal source of the whiteningand staining of the skin and clothing.

Nabial, in U.S. Pat. No. 4,425,328, discloses a stick antiperspirantcomposition including a volatile silicone; a relatively high amount of awaxy matrix, i.e. from about 17 to 30 percent by weight; and asuspending agent to suspend the antiperspirant compound. Nabialspecifically discloses using a clay as a suspending agent for thedisclosed solid compositions. In contrast, the present compositions arestable liquid or flowable semisolid products that effectively resistphase separation by including a relatively low amount of a wax, i.e. upto about 4.5% by weight of the composition. Furthermore, an importantfeature of the present invention is to provide a composition absent aclay suspending agent that stains the skin and clothing.

Davy et al. U.S. Pat. No. 4,126,679 discloses a cosmetic stickcomposition. The Davy et al. composition includes from about 15% toabout 70% of a long chain alcohol having 16 to 22 carbon atoms. The longchain alcohol is a wax, and the relatively high amount of the long chainalcohol suspends the other ingredients in the stick composition. Incontrast, the present liquid or flowable semisolid composition includesno more than about 4.5% by weight of a wax, and, surprisingly, exhibitsessentially no phase separation after long storage periods.

Bissett et al., in European Patent Application No. 88309740.4, disclosepharmaceutical and cosmetic compositions including tocopherol sorbatefor topical application to the skin. The Bissett et al. application isdirected to compositions that protect the skin from the harmful effectsof sunbathing. Bissett et al. do not teach a stable liquid or creamcomposition comprising a topically-active compound and a suspendingagent including a finely-divided silica and a suspending waxcomposition, wherein the composition resists phase separation and isnonwhitening and nonstaining to skin and clothing.

Palinczar, in U.S. Pat. No. 4,724,139, discloses an antiperspirantcomposition including a volatile isoparaffin liquid, a water-insolublewax and an antiperspirant salt. Palinczar includes a minimum of 5% ofthe water-insoluble wax in the composition. In contrast, the presentcomposition includes a wax in a maximum amount of about 4.5% by weight,because greater amounts of a wax provide a solid composition. Thepresent composition is a liquid, a flowable semisolid or a nonflowablesemisolid, having a viscosity in the range of from about 1000 cps(centipoise) to about 100,000 cps, that effectively resists phaseseparation by utilizing a low amount of a wax compound in the suspendingwax composition.

Shin U.S. Pat. No. 4,937,069 discloses an anhydrous semi-solidantiperspirant composition that includes a minimum of 2% by weight fumedsilica; a volatile emollient; a nonvolatile emollient; and a thickener.The composition disclosed by Shin is a cream or gel having a viscosityin the range of 100,000 to 8,800,000 cps (centipoise). The presentcomposition is a liquid or a flowable semisolid including a maximum ofless than 2% by weight finely-divided silica and demonstrating aviscosity in the range of from about 1,000 to about 100,000 cps.

Coopersmith U.S. Pat. No. 3,818,105 discloses that C₁₂ to C₁₄isoparaffinic hydrocarbons, when combined with naphthenic materials, areuseful in a wide range of cosmetic formulations for lubrication of theskin to achieve a quick spreading, non-greasy application withevaporation of the hydrocarbon after use without a greasy buildup. Whilethe hydrocarbons disclosed in the Coopersmith patent lubricate the skinfor better application of the cosmetic formula, the compositions ofCoopersmith do not achieve the unexpected stability achieved inaccordance with the present invention. Other compositions containingvolatile hydrocarbons, such as those disclosed in Bolich U.S. Pat. No.4,472,375, require polymeric water-soluble thickening agents, such asguar gum, to effectively stabilize the compositions.

Similarly, Spitzer et al., in U.S. Pat. No. 4,174,386, disclose anaerosol antiperspirant composition utilizing a volatile hydrocarbonincluding about three or four carbon atoms as the propellant. Thepresent composition also can include a volatile hydrocarbon. However,the hydrocarbons used in the present invention include at least 10carbon atoms and up to about 32 carbon atoms; act as a volatile carrierfor the nonvolatile components of the composition; and then evaporatefrom the skin or hair after topical application of the composition. Thestability of the anhydrous compositions of the present invention,achieved with a new and improved suspending agent including afinely-divided silica and a suspending wax composition, is unexpectedlysuperior to each of the above-identified prior compositions in regard tosyneresis, cosmetic feel and degree of skin and clothing staining.

SUMMARY OF THE PRESENT INVENTION

The present invention is directed to a stable, anhydrous compositioncomprising a topically-active compound; a new and improved suspendingagent comprising a finely-divided silica and a suspending waxcomposition; and a suitable volatile liquid carrier. The suspending waxcomposition comprises a natural or a synthetic wax, like castor wax; avolatile silica or a volatile hydrocarbon; and an aliphatic esterincluding at least 10 to about 32 carbon atoms.

Suspending wax compositions have been used in the paint industry as asuspending agent for pigments. Unexpectedly, it has been found thatincluding a suspending wax composition, comprising a natural orsynthetic wax, like castor wax; a volatile silicone or a volatilehydrocarbon; and an ester including at least 10 carbon atoms to about 32carbon atoms, as an ingredient of the suspending agent in an anhydrous,topically-effective composition of the present invention eliminates theneed for including the traditional organoclay suspending agents. Theanhydrous topically-effective composition is a liquid, flowablesemisolid or nonflowable semisolid composition that includes aparticulate topically-active compound and that has a viscosity in therange of from about 1,000 cps (centipoise) to about 100,000 cps, andpreferably from about 1,000 to about 40,000 cps. To achieve the fulladvantage of the present invention, the topically-effective compositionhas a viscosity in the range of from about 1,000 to about 5,000 cps.Compared to prior anhydrous liquid and semisolid compositions, thepresent topically-effective compositions effectively resist phaseseparation, or syneresis, over a prolonged storage period. Therefore,the topically-effective composition can be used without the need toshake the composition prior to each use in order to redisperse thecomposition ingredients. Surprisingly, it further was found thatesthetic properties, like texture and consistency, or feel, of theantiperspirant composition are improved by masking, reducing, oreliminating the undesirable esthetic properties attributed to thetraditional antiperspirant compounds, such as stickiness.

Another undesirable esthetic, or sensory, property improved by thepresent composition is grittiness. Previous compositions includedrelatively large amount of finely-divided silica, i.e. 2% or greater byweight, in order to sufficiently suspend the particulate ingredientspresent in the composition. However, the new and improved suspendingagent of the present invention utilizes less than 2% by weightfinely-divided silica, thereby effectively overcoming the problem ofgrittiness. Other undesirable esthetic properties reduced or eliminatedby a composition of the present invention include oiliness andlong-drying times caused by high percentages or traditional emollientsand polyols; and whitening and staining of skin and clothing caused byorganoclay suspending agents.

In addition, it has been found that the addition of a suspendingemollient, such as a non-volatile silicone, an aromatic ester, analiphatic ester, a high molecular weight polyol or an oil-solublesurfactant, to an anhydrous topically-effective composition of thepresent invention, further reduces or eliminates phase separation byenhancing the intermolecular bond formation, and therefore thesuspending ability, of the finely-divided silica in the suspendingagent. It should be understood that if an aromatic or aliphatic ester isincluded as the suspending emollient, the aromatic or aliphatic ester isadded to the composition independently from the ester that is present inthe suspending wax composition.

In one important embodiment of the present invention, the anhydrous,topically-effective composition of the present invention incorporates anastringent salt as the topically-active compound to form a stable andefficacious antiperspirant composition. In other embodiments of thepresent invention, the anhydrous, topically-effective compositionincorporates topically effective drugs and medicaments; topicalanesthetics; sunscreen agents; skin-soothing emollients and othertopical cosmetic compounds; topical anti-inflammatories; and the like.The topically-active compound incorporated into the anhydrouscompositions of the present invention can be soluble or insoluble in thevolatile liquid carrier. However, the composition of the presentinvention is especially useful in the topical delivery of particulate,topically-active compounds in that are homogeneously dispersedthroughout the stable, anhydrous composition by the new and improvedsuspending agent.

Accordingly, one important aspect of the present invention to provide ananhydrous, topically-effective composition including either asolubilized topically-active compound or an insoluble and suspendedtopically-active compound dispersed in a suitable, volatile liquidcarrier by a new and improved suspending agent, such that thecomposition is a liquid, a flowable semisolid or a nonflowable semisolidcomposition having a viscosity in the range of from about 1,000 to about100,000 cps, is stable and resists phase separation.

Another aspect of the present invention is to provide a stable,anhydrous, topically-effective composition including a topically-activecompound, a suspending agent comprising a finely-divided silica and asuspending wax composition, wherein the topically-effective compositionincludes less than 2% by weight of the finely-divided silica; and asuitable volatile liquid carrier, wherein the composition has aviscosity in the range of from about 1,000 to about 100,000 cps.

Another aspect of the present invention is to provide an anhydrous,topically-effective composition that efficiently delivers atopically-active cosmetic or medicinal compound upon application to skinor hair.

Another aspect of the present invention is to provide an anhydrous,topically-effective composition useful as an antiperspirant andincluding a volatile silicone or volatile hydrocarbon compound, whereinthe volatile hydrocarbon includes from about 10 to about 30 carbonatoms; an astringent salt; and a suspending agent comprising afinely-divided silica and a suspending wax composition, wherein thecomposition includes less than 2% by weight of the finely-dividedsilica.

Another aspect of the present invention is to provide an anhydrous,topically-effective composition that is not tacky, sticky or grittyduring or after topical application, and that dries relatively quicklyafter topical application.

Another aspect of the present invention is to provide an anhydrous,topically-effective composition that is useful as an antiperspirant andthat demonstrates reduced whitening and staining to the skin and toclothing after topical application.

It is also a further aspect of the present invention to provide ananhydrous antiperspirant composition that exhibits unexpectedly smoothtopical application to the skin; effectively delivers thetopically-active compound; and has superior sensory properties.

Other aspects of the present invention include providing an anhydrous,topically-effective composition for the administration oftopically-active compounds, such as topically effective drugs andmedicaments, topical anesthetics, sunscreen agents, skin-soothingemollients and other topical cosmetic compounds, topicalanti-inflammatories and the like by incorporating the topically-activecompound in an anhydrous composition comprising a new and improvedsuspending agent including a finely-divided silica and a suspending waxcomposition; and a volatile silicone, a volatile hydrocarbon or acombination thereof.

The above and other novel features and advantages of the presentinvention will become more apparent from the following detaileddescription of the preferred embodiments.

DETAILED DESCRIPTION OF THE INVENTION

A stable, anhydrous, topically-effective composition of the presentinvention includes a topically-active compound, such as anantiperspirant compound, like an astringent salt; a suspending agentcomprising a finely-divided silica and a suspending wax composition; anda suitable volatile liquid carrier. The topically-effective compositionis a liquid, a flowable semisolid or a nonflowable semisolid compositionhaving a viscosity in the range of from about 1,000 to about 100,000 cpsthat is applied to the skin or hair. The liquid carrier then evaporatesleaving the topically-active compound and other composition ingredientsin contact with the skin or hair.

In accordance with an important feature of the present invention, theliquid or flowable semisolid composition effectively resists phaseseparation, or syneresis, over long storage periods because of the newand improved suspending agent included in the composition. Therefore,the topically-active composition is available for immediate applicationto the skin or hair without the need to shake or agitate the compositionprior to use in order to redisperse the composition ingredientsthroughout the composition.

The topically-effective composition includes a suspending agentcomprising a finely-divided silica and a suspending wax composition. Thesuspending wax composition comprises a natural or a synthetic wax, likecastor wax; a volatile silicone, a volatile hydrocarbon including fromabout 10 to about 30 carbon atoms or a combination thereof; and an esterincluding at least 10 to about 32 carbon atoms. In accordance with animportant feature of the present invention, the topically-effectivecomposition includes less than 2% by weight of the finely-divided silicaand about 4.5% or less by weight of the natural or synthetic wax.

More particularly, the stable, anhydrous, topically-effectivecomposition of the present invention includes from about 0.01% to about50% by weight of the total composition of a topically-active compound,such as an astringent salt having antiperspirant properties; asuspending agent comprising from about 0.1% to less than 2% by weight ofthe total composition of a finely-divided silica, as a thickening agent,and from about 1% to about 15% by weight of the total composition of asuspending wax composition; and from about 20% to about 98% by weight ofthe total composition of a suitable volatile liquid carrier.

The suspending wax composition included in the suspending agent utilizedin the present invention comprises from about 5% to about 50%, andpreferably from about 25% to about 35%, by weight of a natural wax or asynthetic wax, like castor wax; from about 0.1% to about 94.9%, andpreferably from about 30% to about 50%, by weight of a volatilesilicone, a volatile hydrocarbon including from about 10 to about 30carbon atoms or a combination thereof; and from about 0.1% to about94.9%, and preferably from about 25% to about 50%, by weight of an esterincluding at least 10 carbon atoms to about 32 carbon atoms. A suitableamount of the suspending wax composition is included in thetopically-effective composition, in the range of about 1% to about 15%by weight, such that the amount of natural or synthetic wax in thetopically-effective composition is about 4.5% or less by weight.

The suspending wax composition component of the suspending agent isessential to the efficacy of the present invention and, as will bediscussed more fully hereinafter, the components of the suspending waxcomposition are preblended to form the suspending wax composition beforeadmixing the suspending wax composition with the other ingredients ofthe composition the present invention. It has been found that adding theindividual components of the suspending wax composition to prepare acomposition of the present invention does not effectively reduce oreliminate phase separation of the anhydrous, liquid or flowablesemisolid composition.

Topically-Active Compounds

In accordance with an important feature of the present invention, a widevariety of topically-active compounds can be incorporated into a stable,anhydrous composition of the present invention. Such topically-activecompositions include both cosmetic and medicinal compounds that act uponcontact with the skin or hair. In accordance with another importantfeature of the present invention, the topically-active compound can besolubilized in the composition of the present invention or can behomogeneously dispersed throughout the composition as an insoluble,particulate material. In either case the anhydrous, topically-effectivecomposition of the present invention is resistant to compositionseparation and effectively applies the topically-active compound to theskin or hair. In general, the topically-effective, anhydrouscompositions of the present invention demonstrate essentially no phaseseparation if the topically-active compound is solubilized in thecompositions. Furthermore, if the topically-active compound is insolublein the composition, the anhydrous composition demonstrates essentiallyno phase separation if the insoluble topically-active compound has anaverage particle size less than about 1000μ (microns), and preferablyless than about 100μ, in diameter. To achieve the full advantage of thepresent invention, the topically-active compound has an average particlesize of less than about 10μ in diameter.

The topically-active compound can be a cosmetically-active compound, amedically-active compound or any other compound that is useful uponapplication to the skin or hair. Such topically-active compounds includeantiperspirants, antidandruff agents, antibacterial compounds,antifungal compounds, anti-inflammatory compounds, topical anesthetics,sunscreens and other cosmetic and medical topically-effective compounds.

Therefore, in accordance with an important feature of the presentinvention, the stable, anhydrous topically-effective composition caninclude any of the generally-known antiperspirant compounds such asfinely-divided solid astringent salts like, but not limited to, aluminumchlorohydrate, aluminum chlorohydrox, zirconium chlorohydrate, andcomplexes of aluminum chlorohydrate with zirconyl chloride or zirconylhydroxychloride, either in the presence or absence of an amino acidbuffer such as glycine. In general, the amount of the antiperspirantcompound, such as aluminum zirconium tetrachlorohydrex glycine forexample, in the composition can range from about 0.01% to about 50%, andpreferably from about 0.1% to about 30%, by weight of the totalcomposition. To achieve the full advantage of the present invention, theantiperspirant compound is present in the range of from about 5% toabout 25% by weight.

In addition to antiperspirant compounds, other topically-activecompounds can be included in the anhydrous compositions of the presentinvention in an amount sufficient to perform their intended function.For example, zinc oxide, titanium dioxide or similar compounds can beincluded if the composition is intended to be a sunscreen. Similarly,topically-active drugs, like antifungal compounds; antibacterialcompounds; anti-inflammatory compounds; topical anesthetics; skin rash,skin disease and dermatitis medications; and anti-itch andirritation-reducing compounds can be included in the compositions of thepresent invention. For example, analgesics such as benzocaine, dycloninehydrochloride, aloe vera and the like; anesthetics such as butambenpicrate, lidocaine hydrochloride, xylocaine and the like; antibacterialsand antiseptics, such as povidone-iodine, polymyxin bsulfate-bacitracin, zinc-neomycin sulfate-hydrocortisone,chloramphenicol, methylbenzethonium chloride, and erythromycin and thelike; antiparasitics, such as lindane; deodorants, such as chlorophyllincopper complex, aluminum chloride, aluminum chloride hexahydrate, andmethylbenzethonium chloride; essentially all dermatologicals, like acnepreparations, such as benzoyl peroxide, erythromycin-benzoyl peroxide,clindamycin phosphate, 5,7-dichloro-8-hydroxyquinoline, and the like;anti-inflammatory agents, such as alclometasone dipropionate,betamethasone valerate, and the like; burn relief ointments, such aso-amino-p-toluenesulfonamide monoacetate and the like; depigmentingagents, such as monobenzone; dermatitis relief agents, such as theactive steroid amcinonide, diflorasone diacetate, hydrocortisone, andthe like; diaper rash relief agents, such as methylbenzethonium chlorideand the like; emollients and moisturizers, such as mineral oil, PEG-4dilaurate, lanolin oil, petrolatum, mineral wax and the like;fungicides, such as butocouazole nitrate, haloprogin, clotrimazole, andthe like; herpes treatment drugs, such as9-[(2-hydroxyethoxy)methyl]guanine; pruritic medications, such asalclometasone dipropionate, betamethasone valerate, isopropyl myristateMSD, and the like; psoriasis, seborrhea and scabicide agents, such asanthralin, methoxsalen, coal tar and the like; sunscreens, such as octylp-(dimethylamino)benzoate, octyl methoxycinnamate, oxybenzone and thelike; steroids, such as2-(acetyloxy)-9-fluoro-1',2',3',4'-tetrahydro-11-hydroxypregna-1,4-dieno[16,17-b]naphthalene-3,20-dioneand21-chloro-9-fluoro-1',2',3',4'-tetrahydro-11b-hydroxypregna-1,4-dieno[16z,17-b]naphthalene-3,20-dione.Any other medication capable of topical administration also can beincorporated in an anhydrous composition of the present invention in anamount sufficient to perform its intended function.

Volatile Liquid Carrier

The topically-active compound of the composition is dispersed into anon-aqueous, volatile liquid carrier, such as a volatile silicone or avolatile hydrocarbon. It should be understood that although thecomposition of the present invention is preferably an anhydrouscomposition, it has been found that amounts of water up to about 2% byweight of the composition can be present without adversely affecting thecomposition. The water can be included intentionally or inadvertently asan ingredient in a component of the composition. However, to avoid asticky feeling after application of the topically-effective compositionto the skin, the amount of water should be present at less than 2% byweight, and to achieve the full advantage of the present invention, atless than about 1% by weight of the composition. After topicalapplication of a composition of the present invention, the non-aqueous,volatile liquid carrier facilitates the rapid absorption of thetopically-active compound onto the skin, thereby eliminating the wetfeeling of the carrier vehicle. The volatile liquid carrier then slowlyevaporates, leaving the topically-active compound in contact with theskin.

Suitable non-aqueous volatile liquid carriers useful in the compositionof the present invention include the volatile, low molecular weightpolydimethylsiloxane compounds. The volatile, low molecular weightpolydimethylsiloxane compound can be either a linear or a cyclicpolydimethylsiloxane compound, as long as the polydimethylsiloxanecompound has sufficient volatility to volatilize from the skin aftertopical application of the composition onto the skin. Preferably thepolydimethylsiloxane is a cyclic siloxane, like cyclomethicone. Thevolatile silicones, such as cyclomethicone, feel very rich as they areapplied to the skin, but then evaporate relatively quickly to leave onlythe non-volatile components of the composition on the skin. In general,volatile polydimethylsiloxane compounds useful in the compositions ofthe present invention include polydimethylsiloxane compounds having aviscosity in the range of from about 0.5 cs (centistokes) to about 10cs. The preferred volatile polydimethylsiloxanes have a viscosity in therange of from about 2 cs to about 6 cs.

The cyclic, low molecular weight, volatile polydimethylsiloxanes,designated in the CTFA Cosmetic Ingredient Dictionary. 3rd. Edition(1982) as cyclomethicones, are the preferred siloxanes used in acomposition of the present invention. To achieve the full advantage ofthe present invention, a cyclomethicone used in a composition of thepresent invention is a low viscosity, low molecular weight,water-insoluble cyclic compound having an average of about 3 to about 6--[O-Si(CH₃)₂ ]-- repeating group units per molecule; boil atatmospheric pressure in a range of from about 150° C. to about 250° C.;and have viscosities at 25° C. of from about 2 to about 6 centistokes.The polydimethyl cyclosiloxanes having an average of about 4 to about 5repeating units per molecule, i.e., the tetramer and pentamer, areespecially preferred. Suitable cyclomethicones are availablecommercially under the tradenames SILICONE 344 FLUID and SILICONE 345FLUID from Dow Corning Corporation, Midland, Mich., and SILICONE SF-1173and SILICONE SF-1202 from General Electric, Waterford, N.Y., thetetramer being listed first in each instance.

An example of a linear, low molecular weight, volatilepolydimethylsiloxane compound that is useful in the composition andmethod of the present invention is the compound named in the CTFADictionary as hexamethyldisiloxane, available commercially under thetradename DOW CORNING 200 FLUID from Dow Corning Corp., Midland, Mich.Hexamethyldisiloxane has a viscosity of 0.65 cs, is highly volatile, isnon-greasy, and provides lubrication for topical application to thecomposition of the present invention to the skin. Other linearpolydimethylsiloxanes, such as decamethyltetrasiloxane, having a boilingpoint of about 195° and a viscosity of 1.5 cs; octamethyltrisiloxane;and dodecamethylpentasiloxane, also have sufficient volatility to beuseful in the composition of the present invention. In general, it hasbeen found that a linear, low molecular weight volatilepolydimethylsiloxane compound having a viscosity at 25° C. andatmospheric pressure in the range of from about 0.5 cs to about 5 cs,and a boiling point at atmospheric pressure ranging from about 100° C.to about 250° C., are preferred for use in the composition and method ofthe present invention.

The volatile liquid carrier included in a composition of the presentinvention also can be a volatile hydrocarbon, such as a hydrocarbonincluding from about 10 to about 30 carbon atoms, that has sufficientvolatility to slowly volatilize from the skin or hair after applicationof the topically-effective composition. The volatile hydrocarbonsprovide essentially the same benefits as the volatile silicones, such aslubrication and a rich feel during application.

The preferred volatile hydrocarbon is an aliphatic hydrocarbon includingfrom about 12 to about 24 carbon atoms, and having a boiling point inthe range of from about 100° C. to about 300° C. Exemplary volatilehydrocarbons are depicted in general structural formula (I), wherein nranges from 2 to 5. ##STR1## Specific examples of volatile hydrocarbonsuseful in the anhydrous composition of the present invention include,but are not limited to, the commercially-available compounds PERMETHYL99A and PERMETHYL 101A, corresponding to compounds of general structure(I) wherein n is 2 or 3, respectively, available from PermethylCorporation, Frazer, Pa. A volatile hydrocarbon is useful in thecomposition of the present invention either alone, in combination withanother volatile hydrocarbon, or in combination with a volatilesilicone.

Suspending Agent

The suspending agent of the present composition comprises: (i) afinely-divided silica, and (ii) a suspending wax composition. Thefinely-divided silica used in the suspending agent of the presentinvention helps suspend the particulate topically-active compound in thevolatile liquid carrier; aids in absorbing the volatile liquid carrier;and aids in reducing the preventing composition separation. Thefinely-divided silica is present in a composition of the presentinvention in the range of from about 0.1% to less than 2%, andpreferably in the range of from about 0.1% to about 1.5%., by weight ofthe composition to provide a sufficient composition consistency suitablefor use in a roll-on topically-effective product. To achieve the fulladvantage of the present invention, the finely-divided silica is presentin the range of from about 0.2% to about 1.5% by weight of thecomposition.

Amounts of finely-divided silica in the range of from about 1.5% up toless than 2% by weight of the composition can be used to provide atopically-effective composition having the consistency of a flowablesemisolid that demonstrates thixotropic rheological properties, if theamount of a suspending wax composition included in the composition isnear its lower limit, such as from about 1% to about 5% by weight of thecomposition. Such flowable semisolids exhibit a viscosity in the rangeof from about 5,000 to about 40,000 cps. Including amounts offinely-divided silica in excess of about 2% by weight provides acomposition that has too stiff of a consistency and that has a gritty,and therefore, unpleasant and unacceptable, consistency and feel.

If the amount of the suspending wax composition in the topically-activecomposition is above about 5% by weight, and if the amount offinely-divided silica is in the range of about 1.5% to less than 2% byweight, the topically-effective composition is a nonflowable semisolidhaving a viscosity in the range of from about 40,000 to about 100,000cps. At lower amounts of suspending wax composition and finely-dividedsilica, the topically-effective composition is a liquid having aviscosity of from about 1,000 to about 5,000 cps.

In accordance with an important feature of the present invention, thefinely-divided silica should have an average particle size in the rangeof from about 0.001μ (microns) to about 0.05μ, and preferably in therange of from about 0.005μ to about 0.03μ. To achieve the full advantageof the present invention, the finely-divided silica has an averageparticle size in the range of from about 0.01μ to about 0.02μ. Asuitable finely-divided silica is fumed silica having an averageparticle size ranging from about 0.014μ to about 0.016μ, and availablefrom Cabot Corp., Tuscola, Fla. under the tradename CAB-O-SIL M-5, orfrom DeGussa Corp., Teterboro, N.J. under the tradename AEROSOLCOLLOIDAL SILICA. It also was found that shearing the finely-dividedsilica prior to adding the silica to the volatile liquid carrier vehicleof the present invention further enhanced intermolecular silica bondformation, thereby further contributing to reduced phase separation.

The stable, anhydrous topically-effective compositions of the presentinvention also include from about 1% to about 15%, and preferably fromabout 1.5% to about 10%, by weight of the composition of a suspendingwax composition as a component of the suspending agent. To achieve thefull advantage of the present invention, the topically-effectivecomposition includes from about 1.5% to about 7% by weight of thesuspending wax composition. The suspending wax composition includes fromabout 5% to about 50%, and preferably from about 25% to about 35%, byweight of a natural or a synthetic wax; from about 0.1% to about 94.9%,and preferably from about 30% to about 50%, by weight of a volatilesilicone, a volatile hydrocarbon including from about 10 to about 30carbon atoms or a combination thereof; and from about 0.1% to about94.9%, and preferably from about 25% to about 50%, by weight of an esterincluding at least 10 to about 32 carbon atoms. In accordance with animportant feature of the present invention, the suspending waxcomposition is included in a topically-effective composition of thepresent invention in an amount such that the topically-effectivecomposition includes about 4.5% or less by weight of the natural orsynthetic wax. In accordance with another important feature of thepresent invention, the suspending wax composition is included in atopically-effective composition of the present invention as a pre-blend,as opposed to individually adding the three separate components of thesuspending wax composition to the topically-effective composition.

The suspending wax composition was prepared, for example, by dispersingabout 30 parts by weight of a wax, like castor wax, in a mixturecomprising about 16.5 parts by weight of an ester, like dioctyl adipate,and about 18.5 parts by weight cyclomethicone. The resulting dispersion(phase A) was heated to a temperature above the melting point of thecastor wax, like to about 190° F. (87.8° C.). A room temperature mixture(phase B) comprising about 16.5 parts by weight dioctyl adipate andabout 18.5 parts by weight cyclomethicone was added to the molten phaseA, under continuous high shear stirring, as a thin stream. The additionof the room temperature phase B to molten phase A as a thin stream shockcools the resulting mixture down to a temperature of about 150° F.(65.6° C.) within one minute. The rapid temperature drop seeds themixture, and with continuous high shear, a paste. like suspending waxcomposition useful in a composition of the present invention isprepared.

The wax used in the suspending wax composition can be a natural wax orsynthetic wax, provided the wax is soluble in a hydrophobic carrier,such as a volatile silicone, above the melting point of the wax. Inaddition, the wax should be heat stable and have a sufficiently highmelting point such that the wax precipitates from the hydrophobiccarrier as the hydrophobic carrier cools. The precipitated wax thereforeforms a matrix that helps suspend the insoluble composition ingredientsin the volatile liquid carrier.

Accordingly, the wax provides a degree of rigidity to the suspending waxcomposition. It has been found that specific waxes differ in performancebased upon the melting point and the degree of crystallinity of the wax.Therefore, the amount of wax included in the suspending wax composition,and ultimately in the topically-effective composition, is related to thephysical properties of the wax. Consequently, a wax included in thesuspending wax composition has a melting point of at least 150° F.(65.6° C.), and preferably at least 170° F. (76.7° C.). However, a waxhaving a melting point lower than 150° C. (65.6° C.), such as down toabout 100° F. (37.8° ), can be included as a component of the wax, aslong as this low melting wax is used in combination with a wax having amelting point of at least about 150° F. (65.6° C.).

Therefore, waxes having a melting point of at least 150° F. (65.6° C.)and that improve the rigidity of the suspending wax composition include,but are not limited to, castor wax, beeswax, carnauba wax, ozokeritewax, candellila wax and montan wax. To achieve the full advantage of thepresent invention, castor wax, comprising glyceryltri(2-hydroxystearate), is used as the wax. Castor wax is a hard,high-melting wax that demonstrates good heat stability; is compatiblewith the majority of other waxes; and is an excellent substitute for theexpensive, high-melting natural waxes. Other suitable waxes include, butare not limited to, polyethylene wax, stearic acid, palmitic acid,hydrogenated fats, microcrystalline wax, lanolin wax, polyoxyethylene,bayberry wax, Japan wax, jojoba wax, mink wax, ouricury wax, rice branwax, shellac wax and combinations thereof.

Although a hard wax having a melting point above about 170° F. (76.7°C.) is the preferred wax, a wax that melts above about 150° F. (65.6°C.) and below about 170° F. (76.7° C.) also can be used in thesuspending wax composition. However, a greater amount of the wax thatmelts about 150° F. (65.6° C.) may be needed to achieve the same resultsas a wax that melts above about 170° F. (76.7° C.). In addition, a softwax that melts below about 150° F. (65.6° C.) also can be used as a waxin the suspending wax composition as long as a sufficient amount of awax melting above about 150° F. (65.6° C.) also is included in thesuspending wax composition. Suitable soft waxes that can be used inconjunction with a hard wax include, for example, but are not limitedto, paraffin waxes, cetyl alcohol, stearyl alcohol and spermaceti wax.

Furthermore, it should be understood that the proportion of the wax andthe ester in the suspending wax composition is varied to achieve thedesired consistency of the suspending wax composition depending upon theidentity of the particular wax and the particular ester. In generalhowever, the particular identity of the wax is not critical as long asthe wax provides a smooth and creamy sensory feeling and can beincorporated in to the paste-like suspending wax composition, asdescribed above.

The volatile silicone or volatile hydrocarbon included in the suspendingwax composition is selected from the identical volatile silicones andvolatile hydrocarbons included in the anhydrous, topically-effectivecomposition of the present invention as the volatile liquid carrier. Forexample, volatile silicones that can be included in the suspending waxcomposition include the low molecular weight polydimethylsiloxanecompounds, such as the cyclic polydimethylsiloxane tetramer and thecyclic polydimethylsiloxane pentamer, available commercially under thetradenames SILICONE 344 FLUID and SILICONE 345 LIQUID, respectively,from Dow Corning Corp., Midland, Mich., and SF-1173 and SF-1202,respectively, from General Electric, Waterford, N.Y. A suitable volatilehydrocarbon can be substituted for, or used in conjunction with, thevolatile silicone. Volatile hydrocarbons having from about 10 to about30 carbon atoms, and a boiling point in the range of from about 100° C.to about 300° C., such as, for example, PERMETHYL 99A available fromPermethyl Corp., Frazer, Pa., are suitable for use in the suspending waxcomposition.

An ester also is included in the suspending wax composition. Althoughthe identity of the specific ester, or combination of esters, is notespecially critical, it has been found that a suitable ester includes atleast 10 carbon atoms, and preferably the ester includes from about 10to about 32 carbon atoms. For example, suitable esters include thosecomprising an aliphatic alcohol or an aliphatic polyol including fromabout eight to about twenty carbon atoms and an aliphatic or aromaticcarboxylic acid including from two to about twelve carbon atoms, orconversely, an aliphatic alcohol or polyol including from two to abouttwelve carbon atoms with an aliphatic or aromatic carboxylic acidincluding from about eight to about twenty carbon atoms. A suitableester is either straight-chained or branched; and is a liquid at roomtemperature, having a melting point at about 22° C. or lower.Preferably, the ester has a molecular weight of less than about 500,provides emollient properties, and is soluble in a hydrophobic carrier.Suitable esters therefore include, for example, but are not limited to:

a) aliphatic monohydric alcohol esters, including but not limited to:

myristyl propionate,

isopropyl isostearate,

isopropyl myristate,

isopropyl palmitate,

cetyl acetate,

cetyl propionate,

cetyl stearate,

isodecyl neopentanoate,

cetyl octanoate,

isocetyl stearate;

b) aliphatic di- and tri-esters of polycarboxylic acids, including butnot limited to:

diisopropyl adipate,

diisostearyl fumarate,

dioctyl adipate, and

triisostearyl citrate;

c) aliphatic polyhydric alcohol esters, including but not limited to:

propylene glycol dipelargonate,

propylene glycol laurate,

glyceryl isostearate, and

neopentylglycol dioctanoate;

d) aliphatic alkoxylated esters, including but not limited to:

propylene glycol ceteth-3-acetate, and

propylene glycol isoceteth-3-acetate; and

e) aliphatic esters of aromatic acids, including but not limited to:

C₁₂ -C₁₅ alcohol esters of benzoic acid,

laureth-2 benzoate,

octyl salicylate,

sucrose benzoate, and

dioctyl phthalate.

Numerous other suitable esters are listed in the CTFA CosmeticIngredient Handbook, First Ed. (1988) at pages 24 through 26. Preferredesters include dioctyl adipate, C₁₂₋₁₅ alcohol benzoates, noepentylglycol dioctanoate, isodecyl neopentanoate, cetyl stearate and isocetylstearate. To achieve the full advantage of the present invention,dioctyl adipate is used as the aliphatic ester in the suspending waxcomposition. It should be understood that the straight chain esters(e.g. cetyl stearate) are preferred because straight chain esters arefaster drying than the corresponding branched esters (e.g. isocetylstearate).

Unexpectedly, it was found that including a sufficient amount of thesuspending wax composition in an anhydrous, topically-effectivecomposition of the present invention provides a stable composition thatresists phase separation, and that eliminates the need to include anorganoclay suspending agent. However, the suspending wax compositioncannot introduce more than about 4.5% by weight natural or synthetic waxinto the topically-effective composition because the compositionconsistency becomes too stiff and hard.

The suspending wax composition effectively helps disperse and suspendthe topically-active compound thereby requiring a low amount offinely-divided silica, i.e. below 2%, and often below 1%, by weight, toprovide an essentially syneresis-free, topically-effective compositionhaving a viscosity in the range of from about 1,000 to about 100,000cps, and preferably in the range of from about 1,000 to about 40,000cps. To achieve the full advantage of the present invention thetopically-effective composition has a viscosity in the range of fromabout 1,000 to about 5,000 cps. Accordingly, the composition provides anadded advantage in overcoming the gritty and scratchy feel of atopically-effective composition that includes a finely-divided silica inan amount of 2% by weight or greater. Consequently, thetopically-effective composition is suitable as a cosmetic roll-onproduct that does not require shaking prior to use; that reduceswhitening and nonstaining, and is non-oily after topical application;that dries quickly after topical application; and that exhibits improvedefficacy and sensory properties.

To demonstrate the effect of the finely-divided silica and thesuspending wax composition on the viscosity of composition of thepresent invention, several compositions including varying amounts offinely-divided silica and suspending wax composition were prepared, thenthe viscosity of each composition was determined by standard procedures.The viscosities of the compositions are tabulated below in TABLE I. Thedata in TABLE I shows that the viscosity of the composition can bevaried by adjusting the absoluble and the relative amounts of thefinely-divided silica and the suspending wax composition in thetopically-effective composition. It should be noted however that if theamount of natural or synthetic wax in the topically-effectivecomposition exceeds about 4.5% by total weight of the composition, theviscosity is too high and the composition is too hard, thereby having anunsuitable consistency to perform as a roll-on product. TABLE Iillustrates that the amount of finely-divided silica and suspending waxcomposition in the topically-effective semisolid can be varied toprovide either a liquid composition (Composition F), a flowablesemisolid composition (Compositions A and B), or a nonflowable semisolidcomposition (Compositions C, D and E). Each composition A through Fexhibited essentially no syneresis after extended storage periods, andeach composition was easy to apply and exhibited excellent estheticproperties after application.

                  TABLE I                                                         ______________________________________                                        VISCOSITY OF TOPICALLY-EFFECTIVE                                              COMPOSITIONS                                                                                      % Suspending                                              Composi-                                                                              % Finely-   Wax         Vis.  Vis.                                    tion.sup.1)                                                                           Divided Silica.sup.2)                                                                     Composition.sup.3)                                                                        (24 h).sup.4)                                                                       (7 day).sup.5)                          ______________________________________                                        A       1.9 (by weight)                                                                            3 (by weight)                                                                            23,600                                                                              26,000                                  B       1.9         5           40,000                                                                              43,000                                  C       1.9         10          66,000                                                                              71,000                                  D       1.9         13          76,000                                                                              84,000                                  E       1.9         15          84,000                                                                              90,000                                  F       0.8         2.65         4,700                                                                               4,500                                  ______________________________________                                         .sup.1) Each composition also includes 22% by weight aluminum zirconium       tetrachlorohydrex glycinate as a topicallyactive compound; and includes       cyclomethicone (DOW CORNING 344 FLUID, Dow Corning Corp., Midland, MI.) a     the balance of the composition;                                               .sup.2) CABO-SIL, Cabot Corporation, Tuscola, IL;                             .sup.3) The suspending was composition includes 30% castor wax, 33%           dioctyl adipate and 37% cyclomethicone, by weight;                            .sup.4) Viscosity after 24 hours in cps; and                                  .sup.5) Viscosity after 7 days in cps.                                   

Optional Ingredients

In addition to the essential ingredients, one or more optionalsuspending emollients can be included in a topically-effectivecomposition of the present invention to further aid in the reduction andelimination of phase separation, whitening, and staining; and to furtherimpart favorable sensory properties to the composition. Suitableoptional suspending emollients include, but are not limited to anonvolatile silicone oil, a high molecular weight polyol, an oil-solublesurfactant, an aromatic ester, an aliphatic ester and similar organiccompounds. For example, a composition of the present invention caninclude a compatible skin-soothing suspending emollient such as abenzoate ester of an alcohol having from about 8 to about 30 carbonatoms, like a C₁₂₋₁₅ alcohol benzoate aromatic ester; a nonvolatiledimethylsilicone fluid or a nonvolatile diphenylsilicone fluid; or likecompounds. The suspending emollient, or combination of suspendingemollients, can be present in the topically-effective composition of thepresent invention in an amount ranging from 0% to about 30%, andpreferably from about 5% to about 20%, by weight of the composition. Itshould be understood that if an aliphatic ester is included in thecomposition as an optional suspending emollient, then the aliphaticester is added in addition to, and independent of, the aliphatic esterpresent in the composition as a component of the suspending waxcomposition.

The nonvolatile silicone oil suspending emollient can be a nonvolatiledimethylpolysiloxane fluid or a nonvolatile diphenylsiloxane fluid. Apreferred nonvolatile silicone is a dimethylsiloxane fluid listed in theCTFA Dictionary as a dimethicone and has a viscosity of at least about10 centistokes.

The optional incorporation of a high molecular weight polyol or anoil-soluble surfactant into a topically-effective composition of thepresent invention also aids in the reduction or elimination ofcomposition phase separation, the reduction of whitening and stainingafter composition application and the enhancement of the sensoryproperties of the composition. High molecular weight polyols oroil-soluble surfactants that can be included in a composition of thepresent invention include, but are not limited to, polysorbate 60,polypropylene glycol, decyl pyrrolidone, nonoxynol-2, and similarnonionic surfactants and polyols. Yet another optional suspendingemollient that can be included in a composition of the present inventionis an aromatic ester or an aliphatic ester. Suitable aromatic estersinclude, but are not limited to, laureth-3 benzoate, laureth-2 benzoate,C₁₂ -C₁₅ alcohol benzoates, dioctyl phthalate and sucrose benzoate.Suitable aliphatic esters include those above-described esters that canbe included in the suspending wax composition, such as dioctyl adipate,isocetyl stearate, cetyl stearate, neopentyl glycol dioctanoate andsimilar aliphatic esters.

Furthermore, minor amounts of emollients such as fatty esters, fattyalcohols, mineral oil, polyether siloxane copolymers and the like, alsocan be included in a topically-effective composition of the presentinvention. Usually, such optional emollients are included in amountsranging from 0% to about 10% by weight of the topically-effectivecomposition. Examples of optional emollients include, but are notlimited to PPG-15 stearyl ether, PPG-10 cetyl ether, steareth-10,oleth-8 and PPG-4 lauryl ether.

In addition to the ingredients listed above, the anhydrous,topically-effective compositions of the present invention also caninclude other optional ingredients that are conventionally included intopical cosmetic and medicinal compositions. For example, fragrances canbe incorporated into the anhydrous, topically-effective composition inan amount of from 0% to about 5% based on the total weight of thecomposition. The composition of the present invention, when applied toskin, therefore fixes a substantive fragrance film on the skin thatresists moisture, but that can be removed by washing. Other optionalingredients that can be included in the anhydrous composition of thepresent invention include, but are not limited to, drying agents, liketalc or DRY FLO (aluminum starch octenylsuccinate); preservatives; anddyes. Generally, such optional ingredients are present in a compositionof the present invention in an amount of about 10% or less by weight. Inaddition, although the necessity of including an organoclay is virtuallyeliminated by the use of the new and improved suspending agent, anorganoclay can be included in a composition of the present invention asan additional suspending agent in an amount of up to 20% by weight ofthe composition. An organoclay is especially helpful as an anticakingagent to maintain a particulate topically-effective compoundhomogeneously dispersed throughout the composition. An exemplaryorganoclay is a quaternized three-layer clay exfoliated with a polarsolvent, like a quaternized montmorillonite clay exfoliated withpropylene carbonate.

The following specific examples are illustrative of the anhydrous,topically-effective compositions of the present invention. However, itshould be understood that the present invention is not limited to thespecific examples set forth below. By varying the proportions and thetype of each of the essential ingredients within the above-indicatedranges, a composition of the present invention can be prepared in aliquid, a flowable semisolid or a nonflowable semisolid form. In thefollowing examples, all amounts of the various ingredients are expressedby weight percentages unless otherwise specified. In each of thefollowing examples, the suspending wax composition includes about 30%castor wax, about 37% cyclomethicone, and about 33% dioctyl adipate; andis a paste-like, gel material.

EXAMPLE 1

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.5                                                       Cyclomethicone.sup.2)                                                                             73.5                                                      Aluminum Zirconium  22.0                                                      Tetrachlorohydrex Glycinate.sup.3)                                            Suspending Wax Composition.sup.4)                                                                 3.0                                                       ______________________________________                                         .sup.1) CABO-SIL, Cabot Corporation, Tuscola, IL.                             .sup.2) DOW CORNING 344 FLUID, Dow Corning Corp., Midland, MI.                .sup.3) Wickenol CPS 370, Wickhen Products, Huguenot, NY.                     .sup.4) The suspending wax composition contributes 0.9% castor wax, 1.0%      dioctyl adipate and 1.1% cyclomethicone to the total weight of the            composition. The suspending wax composition was prepared by the method        described above.                                                         

Procedure

The fumed silica was dispersed in the volatile liquid cyclomethicone,and the mixture was thoroughly blended until homogeneous. The aluminumchlorohydrate and the suspending wax composition then were added to thesilica-silicone mixture, and the resulting mixture was charged through acolloid mill for at least two minutes until homogeneous. The resultingcomposition was a flowable semisolid having rheological physicalproperties suitable for use as a roll-on antiperspirant product, such asa viscosity of about 20,000 cps. When topically-applied to the skin, theantiperspirant product was dry to opposed to oily or sticky; and theantiperspirant product exhibited excellent esthetic properties. After anapproximately one year aging period at 27° C., the antiperspirantproduct of Example 1 showed negligible phase separation.

EXAMPLE 2

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.5                                                       Dimethicone.sup.5)  20.0                                                      Cyclomethicone.sup.2)                                                                             53.5                                                      Aluminum Zirconium  22.0                                                      Tetrachlorohydrex Glycinate.sup.3)                                            Suspending Wax Composition.sup.4)                                                                 3.0                                                       ______________________________________                                         .sup.5) SILICONE SF9650, General Electric, Waterford, NY. A nonvolatile       dimethylpolysiloxane fluid included as an optional suspending emollient. 

Procedure

The fumed silica was dispersed in the dimethicone and cyclomethicone,and the mixture was thoroughly blended until homogeneous. The aluminumchlorohydrate and suspending wax composition then were added to thesilica-silicone mixture, and the resulting mixture was mixed at a highshear in a colloid mill until homogeneous. The resulting liquidcomposition possessed suitable physical properties, like a viscosity ofabout 4,000 cps, for use as a roll-on antiperspirant product. Whentopically applied to the skin, the antiperspirant product was dry, asopposed to oily or sticky, and the antiperspirant product exhibitedexcellent esthetic properties. The antiperspirant product showednegligible phase separation after a greater than one year aging periodat 27° C. The viscosity of the composition decreased over this period.

EXAMPLE 3

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.5                                                       C.sub.12 -C.sub.15 Alcohol Benzoate.sup.6)                                                        10.0                                                      Cyclomethicone.sup.2)                                                                             63.5                                                      Aluminum Zirconium  22.0                                                      Tetrachlorohydrex Glycinate.sup.3)                                            Suspending Wax Composition.sup.4)                                                                 3.0                                                       ______________________________________                                         .sup.6) FINSOLV TN, Finetex, Inc., Elmwood Park, NY. An aromatic ester        included as an optional suspending emollient.                            

Procedure

The fumed silica was dispersed in the C₁₂ -C₁₅ alcohol benzoate and thecyclomethicone, and the mixture was thoroughly blended untilhomogeneous. The aluminum chlorohydrate and the suspending waxcomposition then were added to the silica-silicone-benzoate mixture, andthe resulting mixture was charged through a colloid mill for at least 2minutes. The resulting liquid composition possessed physical propertiessuitable for use as a roll-on antiperspirant product. Whentopically-applied to the skin, the resulting antiperspirant product wasdry, as opposed to oily or sticky, and the antiperspirant productexhibited excellent esthetic properties. The antiperspirant productshowed negligible phase separation after an approximately 1 year agingperiod at 27° C.

EXAMPLE 4

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.50                                                      Polysorbate 60.sup.7)                                                                             0.24                                                      C.sub.12 -C.sub.15 Alcohol Benzoate.sup.6)                                                        10.00                                                     Cyclomethicone.sup.2)                                                                             63.26                                                     Aluminum Zirconium  22.00                                                     Tetrachlorohydrex Glycinate.sup.3)                                            Suspending Wax Composition.sup.4)                                                                 3.00                                                      ______________________________________                                         .sup.7) TWEEN 60, ICI Americas, Wilmington DE. An oilsoluble surfactant       included as an optional suspending emollient.                            

Procedure

The fumed silica was dispersed in a blend of polysorbate 60, the C₁₂-C₁₅ alcohol benzoate and the cyclomethicone, then the mixture wasthoroughly blended until homogeneous. The aluminum chlorohydrate and thesuspending wax composition were added to the homogeneous mixture, andthe resulting mixture was charged through a colloid mill for at least 2minutes until homogeneous. The resulting liquid composition possessedphysical properties suitable for use as a roll-on antiperspirantproduct. When topically-applied to the skin, the antiperspirant productwas dry, as opposed to oily or sticky, and the antiperspirant productexhibited excellent esthetic properties. The antiperspirant productshowed essentially no phase separation after an approximately 1 yearaging period at 27° C.

EXAMPLE 5

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.50                                                      Dimethicone.sup.5)  15.00                                                     C.sub.12 -C.sub.15 Alcohol Benzoate.sup.6)                                                        5.00                                                      Cyclomethicone.sup.2)                                                                             53.73                                                     Polysorbate 60.sup.7)                                                                             0.12                                                      Aluminum Zirconium  22.00                                                     Tetrachlorohydrex Glycinate.sup.3)                                            Suspending Wax Composition.sup.4)                                                                 2.65                                                      ______________________________________                                    

Procedure

The fumed silica, dimethicone, and C₁₂ -C₁₅ alcohol benzoate werethoroughly admixed until the fumed silica was uniformly dispersed. Thecyclomethicone and the polysorbate 60 were added to the mixture, and theresulting mixture then was transferred to a colloid mill and mixed for 2minutes until the mixture was homogeneous. The aluminum chlorohydratethen was added, and the composition was mixed until the aluminumchlorohydrate was completely dispersed. The suspending wax compositionthen was added to the mixture, and the resulting mixture was mixed untilhomogeneous. The homogeneous mixture then was returned to the colloidmill and mixed for at least 3 minutes. The resulting compositionpossessed physical properties suitable for use as a roll-onantiperspirant product. When topically-applied to the skin, theantiperspirant product was dry, as opposed to oily or sticky, and theantiperspirant product exhibited excellent esthetic properties. Theantiperspirant product showed no phase separation after a greater thanone year aging period at 27° C.

EXAMPLE 6

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Cyclomethicone.sup.2)                                                                             47.55                                                     Aluminum Zirconium  22.00                                                     Tetrachlorohydrex Glycinate.sup.3)                                            Fumed silica.sup.1) 1.50                                                      Suspending Wax Composition.sup.8)                                                                 2.65                                                      Dimethicone.sup.5)  20.00                                                     Hydrophobic Starch Derivative.sup.9)                                                              1.00                                                      Dioctyl Adipate.sup.10)                                                                           3.50                                                      Fragrance           0.30                                                      Starch/Dextrin Fragrance                                                                          1.50                                                      ______________________________________                                         .sup.8) The suspending wax composition contributes 0.80% castor wax, 0.98     dioctyl adipate and 0.87% cyclomethicone to the total weight of the           composition.                                                                  .sup.9) DRY FLO, National Starch and Chemical Co., Bridgewater, NJ.,          aluminum starch octenylsuccinate.                                             .sup.10) WICKENOL 158, Wickhen Products, Huguenot, NY. An aliphatic ester     included as an optional suspending agent.                                

Procedure

The fumed silica, dimethicone and cyclomethicone were thoroughly admixeduntil the fumed silica was uniformly dispersed. The mixture then wastransferred to a colloid mill and mixed for at least 2 minutes, or untilthe mixture was homogeneous. The aluminum chlorohydrate and thehydrophobic starch derivative then were added to the mixture, and theresulting mixture was blended until both additives were completelydispersed. The suspending wax composition then was added to the mixture,and the resulting mixture was mixed until homogeneous. A premix of thedioctyl adipate and the fragrances then was added to the homogeneousmixture. The resulting mixture was returned to the colloid mill andmixed for at least 3 minutes. The final liquid composition possessedphysical properties suitable for use as a roll-on antiperspirantproduct. When topically-applied to the skin, the antiperspirant productwas dry, as opposed to oily or sticky, and the antiperspirant productexhibited exceptional esthetic properties. The antiperspirant productshowed negligible phase separation after a greater than one year agingperiod at 27° C.

EXAMPLE 7

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Cyclomethicone.sup.2)                                                                             38.13                                                     Aluminum Zirconium  22.00                                                     Tetrachlorohydrex Glycinate.sup.3)                                            Fumed silica.sup.1) 0.80                                                      Suspending Wax Composition.sup.10)                                                                2.65                                                      Polysorbate 60.sup.7)                                                                             0.12                                                      Dimethicone.sup.5)  10.00                                                     C.sub.12 -C.sub.15 Alcohol Benzoate.sup.6)                                                        10.00                                                     Quaternium-18 Hectorite in                                                                        10.00                                                     cyclomethicone.sup.11)                                                        Hydrophobic Starch Derivative.sup.8)                                                              1.00                                                      Dioctyl Adipate.sup.9)                                                                            3.50                                                      Fragrance           0.30                                                      Starch/Dextrin Fragrance                                                                          1.50                                                      ______________________________________                                         .sup.11) BENTONE GEL VS/5 PC, NL Chemicals, Hightstown, NJ., including 75     (by weight) volatile silicone, 5% propylene carbonate and 20% Quaternium1     hectorite.                                                               

Procedure

The fumed silica, dimethicone, cyclomethicone, polysorbate 60 and C₁₂-C₁₅ alcohol benzoate were thoroughly admixed until the fumed silica wasuniformly dispersed. The mixture then was transferred to a colloid milland mixed for at least 2 minutes until homogeneous. The aluminumchlorohydrate and the hydrophobic starch derivative then were added tothe mixture, and the resulting mixture was mixed until the aluminumchlorohydrate was completely dispersed. The suspending wax compositionand the BENTONE GEL then were added to the mixture, and the resultingmixture was mixed until homogeneous. A premix of the dioctyl adipate andthe fragrance then was added to the homogeneous mixture. The resultingmixture was returned to the colloid mill and mixed for at least 3minutes. The composition then was mixed with a turbine propeller untilthe composition was uniform and homogeneous. The composition possessedphysical properties suitable for use as a roll-on antiperspirantproduct. When topically-applied to the skin, the antiperspirant productwas dry, as opposed to oily or sticky, and the antiperspirant productexhibited exceptional esthetic properties. However, because of thepresence of an organoclay, i.e., the BENTONE GEL, this particularantiperspirant product demonstrated increased whitening and staining ofthe skin and clothes. The antiperspirant product showed negligible phaseseparation after a greater than one year aging period at 27° C.

EXAMPLE 8

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.5                                                       Cyclomethicone.sup.2)                                                                             95.0                                                      Aluminum Zirconium  0.5                                                       Tetrachlorohydrex Glycinate.sup.3)                                            Suspending Wax Composition.sup.4)                                                                 3.0                                                       ______________________________________                                    

Procedure

The fumed silica was dispersed in the volatile liquid cyclomethicone,and the mixture was thoroughly blended until homogeneous. The aluminumchlorohydrate and the suspending wax composition then were added to thesilica-silicone mixture, and the resulting mixture was charged through acolloid mill for at least two minutes until homogeneous. The resultingcomposition was a liquid having suitable physical properties, such as a24 hour viscosity of about 3,200 cps and a seven day viscosity of about3,400 cps, for use as a roll-on antiperspirant product. Whentopically-applied to the skin, the antiperspirant product was dry asopposed to oily or sticky; and the antiperspirant product exhibitedexcellent esthetic properties. The composition of Example 8 was a stablesuspension demonstrating essentially no syneresis. Therefore, thecomposition of Example 8, including only 0.5% of the topically-activecompound, demonstrates that it is the suspending agent, comprising thefumed silica and the suspending wax composition, that provides a stabledispersion as opposed to the topically-active compound. The compositionof Example 8 can be compared to the compositions of Examples 1 through7, each including 22% of the topically-active compound, to demonstratethat the suspending agent is the ingredient that provides a stablecomposition of the present invention.

EXAMPLE 9

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Fumed silica.sup.1) 1.9                                                       Cyclomethicone.sup.2)                                                                             73.1                                                      Titanium Dioxide    20.0                                                      Suspending Wax Composition.sup.12)                                                                5.0                                                       ______________________________________                                         .sup.12) The suspending wax contributes 1.5% castor wax, 1.65% dioctyl        adipate and 1.85% cyclomethicone to the total weight of the composition. 

Procedure

The fumed silica was dispersed in the volatile liquid cyclomethicone andthe mixture was thoroughly blended until homogeneous. The suspending waxcomposition then was added to the silica-silicone mixture, and blendeduntil homogeneous. The titanium dioxide was added, and the resultingmixture was charged through a colloid mill for at least two minutesuntil homogeneous. The resulting composition had an initial viscosity ofabout 85,000 cps, and therefore was suitable for use as a semisolidsunscreen product. When topically-applied to the skin, the sunscreenproduct was dry as opposed to oily or sticky; and the sunscreen productexhibited excellent esthetic qualities, with good spreading and coverageproperties.

Alternate volatile silicones, and mixtures of volatile silicones, can besubstituted for the particular volatile silicone carrier vehicle used inthe preceding examples. Similarly, other finely-divided silicacompounds, such as AEROSIL COLLOIDAL SILICA, available from DegussaCorp., Teterboro, NJ., can be substituted for the CAB-0-SIL brand offumed silica.

To demonstrate the importance of including the suspending waxcomposition in a composition of the present invention as a preblend, asopposed to adding the ingredients of the suspending wax compositionindividually, the composition of Example 10 was prepared. The percentageof each individual ingredient included in the composition of Example 10is identical to the percentage of each individual ingredient included inthe composition of Example 1. However, in Example 10, the wax, the esterand the volatile carrier of the suspending wax composition were added tothe topically-effective composition individually as opposed to apreblend prepared by the method described above.

EXAMPLE 10

    ______________________________________                                        Ingredient          % (by weight)                                             ______________________________________                                        Volatile Liquid Carrier.sup.2)                                                                    74.61                                                     Fumed Silica.sup.1) 1.50                                                      Castor Wax          0.90                                                      Dioctyl Adipate     0.99                                                      Aluminum Zirconium  22.00                                                     Tetrachlorohydrex Glycinate.sup.3)                                            ______________________________________                                    

Procedure

The first four ingredients were blended in the above-listed order ofaddition and under high shear. Then the antiperspirant compound wasadded to the homogeneous mixture under shear. It was found that thecomposition of Example 10 lacked the suspension properties and theesthetic properties demonstrated by the composition of Example 1,wherein the components of the suspending wax composition werepreblended. In particular, it was observed that after the composition ofExample 10 was topically applied, discrete, hard particles of castor waxwere perceptible on the skin. In addition, syneresis was observed in thecomposition of Example 10 within a short time after preparation (i.e.within hours), and composition separate further over time.

The anhydrous, topically-effective compositions of the presentinvention, comprising a topically-active compound, like anantiperspirant compound; a suspending agent comprising finely-dividedsilica and a suspending wax composition; and a suitable volatile liquidcarrier, exhibit unique and superior properties upon topicalapplications to skin or hair. The improved physical and sensoryproperties include ultra-dry characteristics, both as to feel and dryingtime; storage stability; elimination of the shaking requirement toredistribute the topically-active compound prior to use; substantiallyreduced whitening of the skin and clothing after topical application;and substantially reduced staining of clothing.

In addition, the new suspending agent of the present invention providesstable, anhydrous topically-effective compositions that effectivelydisperse and suspend insoluble, particulate ingredients and that resistphase separation over a greater than one year storage period.Surprisingly, the suspending agent includes less than 2% of afinely-divided silica and does not require an organoclay compound.Accordingly, the suspending agent improves the esthetics of thetopically-effective composition.

It should be understood that the foregoing detailed description is givenmerely by way of illustration. Obviously, many modifications andvariations of the invention as hereinbefore set forth can be madewithout departing from the spirit and scope thereof and therefore onlysuch limitations should be imposed as are indicated by the appendedclaims.

What is claimed and desired to be secured by Letters Patent is:
 1. Anantiperspirant composition comprising:(a) about 0.01% to about 50% byweight of an antiperspirant compound; (b) from about 20% to about 98.89%by weight of a volatile liquid carrier selected from the groupconsisting of a cyclic volatile silicone having a viscosity of about 0.5to about 10 centistokes, a linear volatile silicone having a viscosityof about 0.5 to about 10 centistokes, a volatile hydrocarbon includingfrom about 10 to about 30 carbon atoms, and combinations thereof; (c)from about 0.1% to less than 2% by weight of a finely-divided silica;and (d) from about 1% to about 15% by weight of a suspending waxcomposition, wherein the suspending wax composition comprises from about5% to about 50% by weight of a wax having a melting point of at least150° F.; from about 0.1% to about 94.9% by weight of a volatile solventselected from the group consisting of a volatile silicone, a volatilehydrocarbon and a combination thereof, wherein said volatile siliconehas a viscosity of about 0.5 to about 10 centistokes and said volatilehydrocarbon includes from about 10 to about 30 carbon atoms; and fromabout 0.1% to about 94.4% by weight of an ester including at least 10 toabout 32 carbon atoms, provided that the composition includes about 4.5%or less by weight of the wax.
 2. The composition of claim 1 wherein thetopically-active compound is an antiperspirant compound.
 3. Thecomposition of claim 2 wherein the antiperspirant compound is anastringent salt selected from the group consisting of an aluminum salt,a zirconium salt, a mixed aluminum zirconium salt, and mixtures thereof.4. The composition of claim 3 wherein the antiperspirant compound isselected from the group consisting of aluminum zirconiumtetrachlorohydrex glycinate, aluminum chlorohydrate, zirconiumchlorohydrate, aluminum chlorohydrex, and mixtures thereof.
 5. Thecomposition of claim 1 wherein the volatile liquid carrier is present inthe range from about 30% to about 75% by weight.
 6. The composition ofclaim 1 wherein the cyclic volatile silicone has a viscosity at 25° C.in the range of from about 2 to about 6 centistokes and a boiling pointat 25° C. and 760 mm in the range of from about 150° C. to about 250° C.7. The composition of claim 7 wherein the cyclic volatile silicone is acyclomethicone.
 8. The composition of claim 8 wherein the cyclomethiconeis selected from the group consisting of hexamethylcyclotrisiloxane,octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane,dodecamethylcyclohexasiloxane, and mixtures thereof.
 9. The compositionof claim 1 wherein the linear volatile silicone has a viscosity at 25°C. in the range of from about 0.5 to about 5 centistokes and a boilingpoint at 2520 C. and 760 mm in the range of from about 100° C. to about250° C.
 10. The composition of claim 10 wherein the linear volatilesilicone is selected from the group consisting of hexamethyldisiloxane,octamethyltrisiloxane, decamethyltetrasiloxane,dodecamethylpentasiloxane, and combinations thereof.
 11. The compositionof claim 1 wherein the volatile hydrocarbon includes from about 12 toabout 24 carbon atoms and has a boiling point at 25° C. and 760 mm offrom about 100° C. to about 300° C.
 12. The composition of claim 12wherein the volatile hydrocarbon has the structural formula: ##STR2##wherein n ranges from 2 to about 5, and mixtures.
 13. The composition ofclaim 1 wherein the finely-divided silica is present in the range offrom about 0.1% to about 1.5% by weight of the composition.
 14. Thecomposition of claim 1 wherein the finely-divided silica has an averageparticle size ranging from about 0.001 to about 0.05 microns.
 15. Thecomposition of claim 1 wherein the finely-divided silica is fumedsilica.
 16. The composition of claim 1 wherein the suspending waxcomposition is present in the range of from about 1.5% to about 10% byweight of the composition.
 17. The composition of claim 1 wherein theester of the suspending wax composition includes from about 12 to about32 carbon atoms.
 18. The composition of claim 1 wherein the ester of thesuspending wax composition is selected from the group consisting ofdioctyl adipate, neopentyl glycol dioctanoate, isodecyl neopentanoate,cetyl stearate, isocetyl stearate, a C₁₂ -C₁₅ alcohol benzoate, andcombinations thereof.
 19. The composition of claim 1 wherein the esterof the suspending wax composition of dioctyl adipate.
 20. Thecomposition of claim 1 wherein the wax of the suspending wax compositionis a synthetic wax, a natural wax or a combination thereof.
 21. Thecomposition of claim 1 wherein the wax of the suspending wax compositionfurther comprises a wax having a melting point of less than 150° F. 22.The composition of claim 1 wherein the wax of the suspending waxcomposition is selected from the group consisting of castor wax,beeswax, carnauba wax, ozokerite wax, hydrogenated lanolin, cocoabutter, polyethylene, stearic acid, plamitic acid, microcrystalline wax,polyoxyethylene, bayberry wax, Japan wax, jojoba wax, mink wax, ouricurywax, rice bran wax, shellac wax, and combinations thereof.
 23. Thecomposition of claim 22 wherein the wax of the suspending waxcomposition is castor wax.
 24. The composition of claim 1 wherein thevolatile silicone of the suspending wax composition has a viscosity inthe range of from about 0.5 to about 6 centistokes and a boiling pointat 25° C. and atmospheric pressure of from about 100° C. to about 250°C.
 25. The composition of claim 1 wherein the volatile hydrocarbon ofthe suspending wax composition includes from about 12 to about 24 carbonatoms and has a boiling point at 25° C. and 760 mm of from about 100° C.to about 300° C.
 26. The composition of claim 1 wherein the volatilehydrocarbon of the suspending wax composition has the structuralformula: ##STR3## wherein n ranges from 2 to about 5, and mixtures. 27.The composition of claim 1 wherein the suspending wax compositioncomprises from about 25% to about 35% by weight castor wax; from about30% to about 50% by weight of a volatile hydrocarbon having thestructural formula: ##STR4## wherein n ranges from 2 to about 5; andfrom about 25% to about 50% by weight of dioctyl adipate.
 28. Thecomposition of claim 1 wherein the suspending wax composition comprisesfrom about 25% to about 35% by weight castor wax; from about 30% toabout 50% by weight of a cyclic volatile silicone, a linear volatilesilicone or a combination thereof; and from about 25% to about 50% byweight dioctyl adipate.
 29. The composition of claim 1 furthercomprising up to about 30% by weight of a suspending emollient.
 30. Thecomposition of claim 29 wherein the suspending emollient is selectedfrom the group consisting of a nonvolatile silicone; an aromatic ester;an aliphatic ester; a high molecular weight polyol; an oil-solublesurfactant; and mixtures thereof.
 31. The composition of claim 30wherein the aromatic ester is a benzoate ester of an alcohol having fromabout 8 to about 30 carbon atoms.
 32. The composition of claim 30wherein the nonvolatile silicone is a dimethicone, a diphenylsiloxanefluid or a combination thereof.
 33. The composition of claim 30 whereinthe high-molecular weight polyol is selected from the group consistingof polyoxyethylene (20) sorbitan monostearate polypropylene glycol andcombinations thereof.
 34. The composition of claim 30 wherein theoil-soluble surfactant is selected from the group consisting of decylpyrrolidone, nonoxynol-2, and combinations thereof.
 35. The compositionof claim 30 wherein the aliphatic ester includes at least 10 to about 32carbon atoms.
 36. The composition of claim 1 further comprising fromabout 0.1% to about 10% by weight of a quaternized three-layer clayexfoliated with a polar solvent.
 37. The composition of claim 36 whereinthe quaternized three-layer clay is a quaternized montmorillonite clayexfoliated with propylene carbonate.
 38. The composition of claim 1further comprising an optional ingredient selected from the groupconsisting of from 0% to about 2% by weight of a drying agent; from 0%to about 10% by weight of an emollient; from 0% to about 5% by weight ofa fragrance; and combinations thereof.
 39. The composition of claim 38wherein the drying agent is aluminum starch octenylsuccinate.
 40. Thecomposition of claim 39 wherein the emollient is selected from the groupconsisting of a fatty ether, a fatty alcohol, a mineral oil, a polyethersiloxane copolymer, and combinations thereof.
 41. The composition ofclaim 1 further comprising up to about 2% water.
 42. An antiperspirantcomposition for application to the skin comprising:(a) from about 0.01%to about 50% by weight of an antiperspirant compound; (b) from about 20%to about 99.83% by weight of a volatile liquid carrier selected from thegroup consisting of a cyclic volatile silicone having a viscosity ofabout 0.5 to about 10 centistokes, a volatile hydrocarbon including fromabout 10 to about 30 carbon atoms and combinations thereof; (c) fromabout 0.1% to less than 2% by weight of a finely-divided silica; and (d)from about 0.05% to about 4.5% by weight of a wax having a melting pointof at least 150° F.; and (e) from about 0.01% to about 13.5% by weightof an ester including at least 10 to about 32 carbon atoms.
 43. Thecomposition of claim 42 wherein the finely-divided silica is present inthe range of from about 0.1% to about 1.5% by weight of the composition.44. The composition of claim 42 wherein the wax is a synthetic wax, anatural wax or a combination thereof.
 45. The composition of claim 42wherein the ester includes from about 12 to about 32 carbon atoms. 46.The composition of claim 42 further comprising from 0% to about 30% byweight of a suspending emollient selected from the group consisting of anonvolatile silicone; an aromatic ester; an aliphatic ester; a highmolecular weight polyol; an oil-soluble surfactant; and mixturesthereof.